30,449 people were registered from administrative databases, and could not declare an ethnicity. It is estimated that the proportion of ethnicities in this group is the same as that of the declared group.[13]

As of a 2012 official survey[14] 40.2% of the population of Orenburg Oblast adheres to the Russian Orthodox Church, 3% declares to be generically Christian (excluding Catholic and Protestant), 2% follows other Orthodox Churches. Muslims constitute 13% of the population. 3% of the population follows Rodnovery (Slavic Paganism), 6.8% follows other religions or did not give an answer to the survey. In addition, 20% of the population declares to be "spiritual but not religious" and 12% to be atheist.[14]

Orenburg Oblast is one of the major agricultural areas of Russia. Its climate is favorable for farming: humid spring, dry summer and a large number of sunny days make perfect conditions for cultivating hard wheat and rye, sunflowers, potatoes, peas, beans, corn, and gourds.

^The density value was calculated by dividing the population reported by the 2010 Census by the area shown in the "Area" field. Please note that this value may not be accurate as the area specified in the infobox is not necessarily reported for the same year as the population.